Aircraft turbomachine

Abstract

Aircraft turbine engine including two coaxial annular walls defining between them a main annular duct for the flow of a primary airflow; —a rotor blading extending radially through the first duct; —an annular separator arranged downstream of the rotor blading and configured to divide the primary airflow into two to form the secondary air flows; —first variable guide vanes which are distributed around the shaft and each comprise a leading edge which is located upstream of the separator and trailing edges which are located in the secondary airflows; —and fixed guide vanes which are distributed around the shaft in the external airflow and downstream of the first variable vanes.

The invention claimed is: 
     
       1. An aircraft turbomachine, comprising
 a gas generator comprising along a longitudinal axis at least one compressor, a combustion chamber and at least one turbine, 
 two coaxial annular walls, including an internal wall and an external wall, the internal wall and the external wall extending around each other and defining therebetween a main annular flow duct for a main air flow, 
 a rotor blading extending radially across said first main annular flow duct, 
 an annular separator arranged downstream of the rotor blading and between the internal wall and the external wall, the separator defining, with the internal wall and the external wall respectively, two secondary annular flow ducts including an internal secondary annular flow duct and an external secondary annular flow duct, the internal secondary annular flow duct for an internal secondary air flow and the external secondary annular flow duct for an external secondary air flow, the separator comprising, at an upstream end, an annular splitter nose configured to split the main air flow to form the internal secondary air flow and the external secondary air flow, and 
 stator elements extending radially through each of the main annular flow duct, the internal secondary annular flow duct, and the external secondary annular flow duct, 
 
       wherein said stator elements comprise first variable pitch straightener vanes, the first variable pitch straightener vanes are distributed around said axis, the first variable pitch straightener vanes each comprise a leading edge located upstream of said splitter nose, an internal trailing edge located in the internal secondary annular flow duct, and an external trailing edge located in the external secondary annular flow duct, and 
       the turbomachine further comprises secondary straightener vanes that are distributed about said axis in the external secondary annular flow duct and downstream of the external trailing edges of said first variable pitch straightener vanes, each of the secondary straightener vanes comprising a stationary portion and a movable portion with a variable pitch. 
     
     
       2. The turbomachine according to  claim 1 , wherein the stator elements further comprise second variable pitch straightener vanes that are located in said internal secondary annular flow duct. 
     
     
       3. The turbomachine according to  claim 2 , wherein the second variable pitch straightener vanes comprise leading edges and trailing edges, the leading edges of the second variable pitch straightener vanes being located directly downstream of the internal trailing edges of the first variable pitch straightener vanes, and being separated by predetermined axial clearances (J) from said trailing edges of the first variable pitch straightener vanes. 
     
     
       4. The turbomachine according to  claim 3 , wherein said predetermined axial clearances are less than 10 mm. 
     
     
       5. The turbomachine according to  claim 2 , wherein a total number of said second variable pitch straightener vanes is equal to A) a total number of said first variable pitch straightener vanes or, B) a multiple of the total number of said first variable pitch straightener vanes. 
     
     
       6. The turbomachine according to  claim 1 , wherein the secondary straightener vanes that are at least partly stationary comprise leading edges separated by a predetermined axial clearances (I) from said trailing edges of the first variable pitch straightener vanes. 
     
     
       7. The turbomachine according to  claim 1 , wherein a total number of said secondary straightener vanes that are at least partly stationary is equal to A) a total number of said first variable pitch straightener vanes or, B) a multiple of the total number of said first variable pitch straightener vanes. 
     
     
       8. The turbomachine according to  claim 1 , wherein the turbomachine further comprises at least one control system for controlling an angular pitch of the variable pitch straightener vanes. 
     
     
       9. The turbomachine according to  claim 8 , wherein said control system is mounted within said separator or radially outside said external wall. 
     
     
       10. The turbomachine according to  claim 1 , wherein at least some of said secondary straightener vanes that are at least partly stationary, have different profiles from vanes of the first variable pitch straightener vanes. 
     
     
       11. The turbomachine according to  claim 1 , wherein the rotor blading is a fan or a compressor rotor blading. 
     
     
       12. The turbomachine according to  claim 1 , wherein each of the secondary straightener vanes comprises an upstream portion with variable pitch including a leading edge, and a stationary downstream portion comprising a trailing edge. 
     
     
       13. The turbomachine according to  claim 1 , wherein said secondary straightener vanes that are at least partly stationary comprise an intrados and an extrados, and said first variable pitch straightener vanes comprise an intrados and an extrados.